1. Field of the Invention
The present invention relates, in general, to the field of view navigation of mobile computing and communication hand-held devices utilizing an information display, and more particularly, to a view navigation guidance system that assists the user in guiding the navigation of the information display.
2. Description of the Related Art
Hand held devices with a small physical display often must show a virtual stored or computed contents display that is larger than the screen view of the physical display. Only a portion of the virtual display can be shown at any given time within the screen view, thus requiring an interactive process of view navigation that determines which particular portion of the virtual display is shown. This process must allow the user to scroll the entire virtual display. Various methods have been used to control view navigation, including keyboards, joysticks, touch screens, voice commands, and rotational and movement sensors. Since the user can see only the screen view, there is a need for an efficient guidance system to indicate to the user what portion of the virtual display is currently shown and which direction should the user scroll the screen view.
U.S. Pat. Nos. 5,510,808, 6,008,807 and 6,014,140, together with the references stated in these patents, describe the well known prior art scrollbar method for guiding view navigation. In this method, horizontal and vertical scrollbars, typically placed on the bottom and right boundaries of the display, indicate the relative position and size of the screen view to the virtual display. As the user scrolls the display, the scrollbars change to reflect the new position of the screen view. In application where the virtual display size changes dynamically the length of each scrollbar slider changes to reflect the relative width and height of the screen view compared to the virtual display.
Scrollbars view navigation guidance generally works well with large stationary displays. However, it exhibits major disadvantages for smaller displays used in hand held devices. The first disadvantage is that the user must look at both scrollbars in order to determine the screen view position within the virtual display. It is even more difficult for the user to determine the relative size of the screen view compared to the size of the virtual display since the user must assimilate the width information separately from the horizontal bar and the height information separately from the vertical bar.
Another disadvantage is that the scrollbars consume some valuable screen view spaces. For example, in a typical smartphone with a 320×480=153600 pixels screen view, the scrollbars may reduce the usable screen to 300×460=138000 pixels, that is a reduction by 10%.
U.S. Pat. No. 7,467,356 describes a graphical user interface that includes a mini-map area that is placed on the display near the main information pan. The mini-map conveys a lot of information and therefore it must be placed in a separate and dedicated area that cannot be used for contents display. This poses a major disadvantage for small displays where every pixel is important and cannot be assigned exclusively for view guidance.
Originally, heads-up display (HUD) was developed for use in fighter airplanes where various data is projected on the front window so that the pilot can view both the projected data and the battlefield scene simultaneously. In the context of video games and virtual displays that use a stand-alone physical display, a heads-up display (HUD) is a partially transparent graphical layer containing important information placed on top of all the other graphical layers of the application information contents. All graphical layers are combined in vertical order for rendering in the physical display, giving the HUD layer a perceived affect of being on top. The HUD layer is assigned a transparency parameter Alpha which is varied from 0 (invisible) to 1 (fully opaque).
U.S. Pat. No. 7,054,878 illustrates the use of heads-up display on a desktop computer. U.S. Pat. No. 7,115,031 illustrates combination of local game view and common game view with multiple players, where the common game view is transparently rendered as HUD on top of the local game view. An article titled “Multimedia presentation for computer games and Web 3.0”, by Ole-Ivar Holthe in IEEE MultiMedia, December 2009, discusses modern use of in-game head-up displays. Geelix HUD , an in-game Heads-Up Display for sharing game experiences with other users, is available from www.geelix.com. Version 4.0.6 first seen on internet Sep. 20, 2007. Use of HUD in gaming is described in Wikipedia at http://en.wikipedia.org/wiki/HUD (video gaming), while the concept of mini-map is shown in http://en.wikipedia.org/wiki/Mini-map.
Use of HUD display heretofore known suffer from a number of disadvantages. First, the HUD layer optically obstructs important contents data, which is a bigger problem in the small display of hand-held devices. Secondly, the HUD layer tends to grab user's attention, thus becoming a perceptual distraction to the user.